Anthropogenic (Man Made Material)

Peridot (Olivine)

Olivine ((Mg,Fe)2SiO4)

Quartz (chalcedony variety) or Limestone with Quartz Veins

SiO2 (for Quartz/Chalcedony); CaCO3 (for Limestone)

Quartz Geode (likely within Limestone or Dolomite matrix)

Quartz (SiO₂)

Orange Calcite

Calcite (Calcium Carbonate, CaCO3)

Agate (or Banded Agate)

Agate (a variety of Chalcedony, which is a cryptocrystalline form of Quartz); Chemical Formula: SiO₂ (Silicon Dioxide)

Shale (possibly)

Shale (fine-grained clastic sedimentary rock)

Quartz

Quartz (SiO₂)

Sandstone (likely a river or beach pebble)

Sandstone (a clastic sedimentary rock)

Quartz (Milky Quartz)

Quartz (SiO2 - Silicon Dioxide)

Caliche (also known as hardpan, calcrete, kankar)

Primarily composed of calcium carbonate (CaCO₃), often mixed with other minerals like quartz, clay minerals, and iron oxides.

Quartz

Quartz (SiO₂ - Silicon Dioxide)

Amazonite

KAlSi3O8 (Potassium Feldspar, variety of Microcline)

Shale

Shale

Biotite Mica

Biotite (K(Mg,Fe)3AlSi3O10(F,OH)2)

Shale

Shale (clastic sedimentary rock)

Fossil Coral

Coral Limestone (a type of biogenic sedimentary rock)

Sandstone

Sandstone (composed primarily of sand-sized minerals or rock grains)

Azurite-Malachite (often a mixed specimen)

Azurite: Cu3(CO3)2(OH)2; Malachite: Cu2(CO3)(OH)2. The specimen appears to be a natural mixture or intergrowth of these two minerals.

Granite Pebble

Granite (a plutonic igneous rock composed primarily of quartz, feldspar, and mica/amphibole)

Moonstone (bead form)

Potassium Aluminum Silicate (KAlSi3O8) - a variety of Orthoclase Feldspar

Quartzite

Quartzite (SiO2)

Soapstone

Steatite (primarily composed of Talc, Mg₃Si₄O₁₀(OH)₂)

Granite (weathered/river-tumbled)

Granite (Plutonic Igneous Rock)

Clear Quartz (or Rock Crystal)

Quartz (SiO₂)

Quartz with Iron Stains

Quartz (SiO2) with iron oxide/hydroxide staining

Granite

Granite (a felsic intrusive igneous rock)

Halite

Halite (NaCl)

Quartz (milky quartz variety)

Quartz (SiO₂)

Sodalite (blue beads) and Clear Quartz (clear beads)

Sodalite: Na4Al3Si3O12Cl; Quartz: SiO2

Granite

Granite (a felsic intrusive igneous rock)

Red Tiger's Eye beads

Tiger's Eye (variety of Chalcedony, SiO2)

Garnet (likely Pyrope or Almandine)

Garnet Group (complex nesosilicate minerals, e.g., Pyrope Mg3Al2(SiO4)3, Almandine Fe3Al2(SiO4)3, Spessartine Mn3Al2(SiO4)3, Grossular Ca3Al2(SiO4)3, Andradite Ca3Fe2(SiO4)3, Uvarovite Ca3Cr2(SiO4)3). The vivid red color in the image strongly suggests Pyrope or Almandine.

Shale or Slate with Quartz Veins

Shale (fine-grained clastic sedimentary rock) or Slate (low-grade metamorphic rock formed from shale) with Quartz (SiO2) veins

Chalcedony (Banded/Mottled Variety)

Chalcedony (a cryptocrystalline variety of Quartz, SiO2)

Zircon

Zircon (ZrSiO4)

Quartz (likely Jasper or Chert variety)

Quartz (SiO₂)

Carnelian

Carnelian (a variety of Chalcedony, SiO2)

Aventurine

Aventurine Quartz (SiO2 with inclusions)

Quartzite

Quartzite (primarily SiO2)

Granite

Granite (a plutonic igneous rock)

Banded Jasper (Chert)

Silicon Dioxide (SiO2) - variety of Chalcedony

Rutilated Quartz

SiO2 (Quartz) with TiO2 (Rutile inclusions)